The present invention relates to an automatic urine disposal device and a urine receptacle used for that purpose worn by the elderly with difficulty walking, hospitalized patients, physically disabled people, and others who are unable to voluntarily control the bladder or to clean up urine on their own.
In general, elderly, physically disabled people, and those who are hospitalized due to injuries or illness sometimes become unable to voluntarily control the bladder or clean up urine on their own. In those situations, generally, a catheter is directly inserted into the bladder to discharge urine or a paper diaper is used.
When a catheter is directly inserted into the bladder, the wearer feels great discomfort and there is also the probability of injuring the urethra or bladder or the occurrence of an infection. Thus, expertise as well as the use of special sterilized utensils is required.
Prolonged use of a paper diaper may cause urine leakage, feeling of discomfort, humidity inside the diaper, or skin troubles such as rashes. To avoid this, the paper diaper must be frequently changed, which will impose considerable physical and mental burdens on both the wearer and the caretaker. Imposed on a daily basis, those physical and mental burdens become a big concern and a significant economical burden as well.
In order to solve the problems listed above, an automatic urine disposal device, which uses a urine receptacle and a vacuum pump to suction urine and then to direct the urine into a urine tank via a urine drainage tube, has been developed. A urine detection sensor for detecting urination and activating the vacuum pump is used in such an automatic urine disposal device. As for the urine detection sensor, there are various methods available for urine detection such as: detection based on electric conduction of a pair of electrodes as a result of urination; detection based on changes in pressure inside the urine drainage tube as a result of urination; and detection based on detection of odor components in excretory substances. Detection based on changes in pressure inside the urine drainage tube as a result of urination and detection based on detection of odor components in excretory substances will make the device complicated and thus expensive. Therefore, for practical use, urine detection based on electric conduction of a pair of electrodes has been considered effective.
Automatic urine disposal devices with a urine detection sensor using a pair of electrodes have been disclosed in Japanese Application Patent Laid-open Publications No. Hei 07-171182 and No. Hei 10-85275.
The urine receptacle of an automatic urine disposal device has a urine absorbing sheet below a top sheet made of a nonwoven fabric which lets urine easily pass. A pair of electrodes, constituting a urine detection sensor, is located between the top sheet and urine absorbing sheet. Below the urine absorbing sheet, urine absorbing space forming material for defining a urine flow path is provided in order to collect urine from a large area. Sometimes the urine absorbing sheet or the urine absorbing space forming material fails to collect urine and the urine there remains uncollected. This may cause the uncollected urine to ooze toward the urine detection sensor when the wearer changes his/her posture or when his/her weight is shifted.
The urine detection sensor with a pair of electrodes becomes electrically conductive due to the residual urine oozing out, detects presence of urine, and activates the vacuum pump. If the vacuum pump becomes activated in this manner when the wearer is not urinating, the wearer feels discomfort, thus creating a problem that he/she cannot use it comfortably.